Impact and ESG Frameworks: Choosing IMP, IRIS+, or SDGs

Why the framework question keeps circling back

Family offices with serious impact programmes often describe a familiar cycle. A principal returns from a philanthropy conference convinced that SDG alignment is the only language development finance institutions speak. Six months later, a potential co-investment partner insists on Impact Management Project dimensions. Meanwhile, the investment team quietly built its own spreadsheet using a handful of IRIS+ metrics. The result is three partial frameworks running simultaneously, none applied with enough discipline to generate useful data.

This is not a niche problem. Research across multi-family and single-family offices consistently finds that fewer than a third of those claiming an impact mandate can produce a consistent, time-series dataset on even five impact metrics. The issue is almost never a shortage of frameworks. It is a shortage of commitment to any one of them.

A theoretically inferior framework applied consistently for three years produces more actionable insight than a theoretically superior one reviewed annually and never fully implemented.

The four frameworks and what each actually does

Before choosing, a family office needs an honest account of what each framework was designed to do, because the marketing around all four tends toward universalism that the underlying architecture does not support.

Impact Management Project: the analytical backbone

The IMP, developed through a global practitioner consensus process beginning around 2016, organises impact assessment along five dimensions: What (the outcome and its importance), Who (the stakeholders affected and their relative deprivation), How Much (scale, depth, and duration), Contribution (whether the investment caused the outcome or would it have occurred anyway), and Risk (the probability that impact is lower than expected). These five dimensions are not a scorecard. They are a structured interrogation of causality and materiality.

IMP also introduced a widely used spectrum running from impact avoidance through benefit to stakeholders to contributing to solutions, a taxonomy that helps investment committees articulate where in the impact distribution a given position sits. Its practical limitation is that it provides structure without standardised metrics. Two analysts applying the five dimensions to the same investment can reach different conclusions if the underlying data inputs differ. This is a feature for sophisticated users who want analytical flexibility, and a bug for organisations that need comparability across a large portfolio.

IRIS+: the metrics library

IRIS+, maintained by the Global Impact Investing Network, is best understood as a standardised catalogue rather than a framework. It contains several hundred defined metrics organised by sector, covering areas from financial services to agriculture to healthcare. The catalogue allows different funds and portfolio companies to report against identical definitions, which is the precondition for aggregating impact data across a portfolio or a fund-of-funds structure.

IRIS+ integrates with IMP by suggesting which metrics are most relevant for each of the five dimensions, and it maps to SDG targets where the connection is defensible. Its limitation is the opposite of IMP's: IRIS+ can generate substantial volumes of standardised data while providing little guidance on whether the underlying activities are actually causing the outcomes being measured. A portfolio company can report IRIS+ metric PI9420 (number of smallholder farmers reached) meticulously without that number saying anything meaningful about whether those farmers are better off.

SDG alignment: the communication layer

The United Nations Sustainable Development Goals were not designed as an investment framework. They were negotiated as a political commitment among member states in 2015, comprising 17 goals and 169 underlying targets. Their adoption by the investment community reflects a pragmatic need for a shared vocabulary that bridges development finance, philanthropy, and commercial capital rather than any analytical superiority.

SDG alignment is the most efficient way to communicate impact intent to a broad external audience, including family members across generations, co-investors, and regulators in jurisdictions that have mapped their own sustainable finance taxonomies to the SDG structure. The European Union's Taxonomy Regulation, for instance, is partially anchored to SDG-derived concepts. The limitation is the inverse of its communicative strength: almost any investment can be mapped to one or more SDGs at a sufficient level of abstraction, which makes the framework nearly useless for distinguishing between investments with genuinely different impact profiles.

TCFD: the climate risk sidecar

The Task Force on Climate-related Financial Disclosures, established by the Financial Stability Board in 2015 and now absorbed into the ISSB framework through IFRS S2, operates in a different register from the three frameworks above. TCFD addresses how climate-related physical and transition risks affect the financial value of assets, not whether those assets produce positive outcomes for society. Governance, strategy, risk management, and metrics and targets are its four disclosure pillars.

TCFD should sit alongside an impact framework, not inside it. A family office with a clear IMP-based impact policy still needs a separate TCFD-aligned climate risk analysis for its private equity and real asset positions. The regulatory convergence happening through ISSB, the EU Corporate Sustainability Reporting Directive, and equivalent rules in the United Kingdom and Australia means that family offices with significant operating company holdings or fund structures will face mandatory or quasi-mandatory TCFD-derived disclosure obligations regardless of whether they have a voluntary impact programme.

A practical framework for choosing a framework

The selection question is not which framework is theoretically superior. It is which framework fits the family office's actual portfolio composition, governance capacity, and communication objectives. Three questions structure the choice.

Where does the portfolio sit on the public-private spectrum?

A family office with 70 percent or more of its impact assets in listed equities is primarily making allocation and engagement decisions. In that context, SDG alignment provides a defensible, externally legible rationale for tilts and exclusions, and IRIS+ metrics are largely inapplicable because the office does not control the underlying data collection. Conversely, a family office deploying direct equity into growth-stage enterprises in emerging markets, or investing through impact-first private credit structures, has the leverage to require portfolio companies to report IRIS+ metrics and the incentive to apply IMP's contribution dimension rigorously, because understanding additionality matters when capital is genuinely scarce.

How large is the team, and who owns measurement?

IMP's five-dimension analysis requires someone who can conduct it consistently. For a family office with a dedicated impact officer or a two-person impact team, IMP provides the right level of rigour. For a family office where impact assessment is one of seven responsibilities of a generalist analyst, IRIS+ provides guardrails that reduce dependence on individual analytical judgment. The framework should fit the team, not the other way around.

Who is the primary reporting audience?

If the family office's principal reporting obligation is to a rising generation of family members who want to understand whether the portfolio is aligned with global sustainability goals, SDG mapping with selective IRIS+ metrics provides the most accessible narrative. If the primary audience is institutional co-investors or development finance institution partners who conduct their own impact due diligence, IMP alignment is a prerequisite for productive dialogue. If regulators in the EU or UK are a material audience, SFDR article classification and TCFD disclosure are non-negotiable additions.

The documented policy: what it must contain

Choosing a framework is necessary but not sufficient. The choice must be codified in a document that functions as a standing instruction to the investment team. A credible impact framework policy should contain four elements.

First, a framework declaration: a single sentence stating which framework governs impact assessment for new investments, with explicit acknowledgment that other frameworks may be used for communication purposes but not for investment decisions. Second, a minimum data set: the specific metrics, whether IRIS+ catalogue entries or IMP dimension assessments, that must be completed before any impact investment proceeds to investment committee. Third, a review schedule: the framework should be reviewed against the portfolio and against regulatory developments on a fixed annual basis, with a documented rationale required to change it. Changing frameworks should carry a governance cost, which creates the right incentive to choose carefully the first time. Fourth, a reporting template: a standardised output format that produces comparable data across years, allowing the principal to observe whether the portfolio's aggregate impact profile is improving, deteriorating, or stable.

The impact framework policy is not a marketing document. It is an internal governance instrument. Its audience is the investment committee, not the family newsletter.

Regulatory convergence and what it means for voluntary adopters

The regulatory environment is moving toward mandatory non-financial disclosure at a pace that would have seemed implausible before 2020. The EU SFDR, which requires fund managers to classify products as article 6, 8, or 9 depending on their sustainability characteristics, has forced a degree of definitional rigour that the voluntary impact community had long resisted. ISSB's IFRS S1 and S2, effective for reporting periods beginning January 2024 in several jurisdictions, create a global baseline for sustainability and climate disclosure that is increasingly being adopted or referenced by regulators outside the EU, including in Singapore, Japan, and Canada.

Family offices sitting outside mandatory scope should treat this convergence as a planning constraint rather than an irrelevance. A family office that builds its impact programme around SDG alignment alone, with no connection to ISSB or SFDR concepts, will face a meaningful translation cost when a co-investor or downstream fund manager requests SFDR-compatible data. A programme built on IMP and IRIS+ foundations maps more cleanly to SFDR's principal adverse impact indicators and to ISSB's sector-based disclosure requirements. The governance premium for choosing the right framework today is, in effect, an option on regulatory optionality tomorrow.

A recommended baseline for most family offices

For a family office with a mixed portfolio of private impact investments and listed sustainable equities, a pragmatic baseline combines IMP's five-dimension structure as the analytical framework for investment decisions, a curated set of 10 to 20 IRIS+ metrics matched to the portfolio's primary sectors, SDG mapping as the output layer for family and external communication, and a separate TCFD-aligned climate risk register updated annually. This combination does not require building a specialist team from scratch. It requires committing to the structure, training the investment team on IMP's contribution and risk dimensions specifically, and resisting the temptation to add a sixth framework when a new one gains traction at a conference.

The single most common mistake among family offices with genuine impact ambitions is treating framework selection as a recurring decision rather than a one-time governance choice subject to disciplined annual review. The frameworks themselves are publicly available, extensively documented, and largely stable. The scarce resource is not information about them. It is the organisational discipline to pick one and use it for every impact decision, year after year, until the data accumulates into something that can actually inform judgment.